DVDs become common as optical discs onto which various information such as main picture (video), audio, sub picture, reproduction control information and so on is recorded. According to a DVD standard, main picture information (video data), audio information (audio data) and sub picture information (sub picture data) are respectively packetized with the reproduction control information (navigation data) and multi-recorded onto a disc in a program stream format of MPEG 2(Moving Picture Experts Group phase 2), which is a high performance encoding technology. Among them, the main picture information has data, which is compressed in a MPEG video format (ISO 13818-2), for one stream in one program stream. On the other hand, the audio information is recorded in a plurality of formats (i.e. linear PCM, AC-3, MPEG audio and so on) and has data for up to 8 streams in one program stream. The sub picture information is defined by a bitmap, and is compressed and recorded in a run length method, and has data for up to 32 streams in one program stream. Thus, in DVDs, by employing the program stream format, a plurality of selectable streams of the audio information (e.g. stereo audio stream or surround audio stream, original English audio stream, Japanese dubbing audio stream, and so on) and a plurality of selectable streams of the sub picture information (e.g. Japanese caption stream, English caption stream and so on) are multi-recorded for one stream of the main picture information in one movie for example.
On the other hand, recently, a transport stream of MPEG2 standard is coming to be standardized, which is suitable for larger volume or higher speed data transfer. According to the transport stream format, a plurality of elementary streams are transferred at the same time at a far higher transfer rate than the aforementioned program streams format. For example, a plurality of programs, such as a plurality of satellite digital broadcasting channels in one satellite radio wave, are transmitted at the same time in a TDM (Time Division Multiplex) scheme. That is, in the transport stream format, a plurality of elementary streams each having a large amount of data can be multiplexed in the TDM scheme and transferred, for example, a plurality of movies to be recorded in a plurality of DVDs can be transferred at the same time.